The present invention is related to an improved electronic component, and particularly a multi-layered ceramic capacitor (MLCC), which allows for improved manufacturing efficiency. More specifically, the present invention relates to an improved MLCC comprising an identification (ID) mark which is integral to the MLCC, and permanent, thereby eliminating the impact of abrasive processes.
MLCC'S are well known and widely used in the electronics industry. MLCC's can be quite small yet they are typically symmetrical in geometry thereby allowing for use in pick and place machinery as is well known in the art. Unfortunately, the requirement that MLCC's be compatible with pick and place machines has limited the technology suitable for use in an MLCC as any advance must maintain the geometrical symmetry.
Most electronic parts requiring proper orientation are marked during manufacture and the marking is identified by the pick and place machinery thereby allowing proper orientation. Unfortunately, MLCC's are made in very large volumes starting with the lamination of many interleaved layers of active electrode layers and ceramic followed by, dicing, abrasive treatment, and termination whereby the internal orientation of the various layers is no longer discernible. By way of example, MLCC's are typically made by laminating large sheets which are then fired at high temperature to sinter the ceramic. The large sheets are then cut, or diced, to form the individual MLCC's, which may be no more than a mm in any dimension, and the individual MLCC's are then tumbled in abrasive medium to remove any rough edges prior to further processing. Any attempt to provide an orientation mark on the surface would not survive the furnace and, if it did, would not survive the abrasive treatment. Even if one could determine the orientation, and provide an orientation mark after dicing, the mark would not survive the abrasive treatment and the many millions of parts formed simultaneously eliminates the realistic possibility of marking individual capacitors after manufacturing.
Those of skill in the art have therefore been limited in MLCC design to those geometries and arrangements which can be mounted in any orientation. This has mitigated the possibility of asymmetrical MLCC's in large scale use.
The present invention provides a method of forming an MLCC with an ID mark for orientation wherein the mark is permanent, observable after firing, tumbling and finishing and which does not consume space of the capacitive couple of the capacitor.